Research indicates that the media play a role in shaping the information that voters have about election options. Knowledge of those options has been related to actual vote, but has not been shown to be strongly related to uncertainty. Uncertainty, however, does seem to motivate voters to engage in communication activities, some of which may influence their voting decisions. Data gathered in a telephone survey of registered voters prior to elections in Columbus, Ohio, in November 1983 were used to determine the role of knowledge and uncertainty in voter decision making. Results indicated that high media use led to knowledge of pro and con arguments about issues and candidates, and that such knowledge was predictive of voting intentions. Voters high in such knowledge were less uncertain in their electoral choices. Voters' motivations for following the campaign, however, did not act as contingent conditions for the media use, knowledge, and uncertainty linkage. (FL)